Apparatus for the fluid treatment of photographic sheet material wherein the latter is passed along an array of rollers

ABSTRACT

An apparatus for the treatment of sheet material, especially photographic sheets, comprises a multiplicity of surfaces or a single surface movable in a transport direction and defining a transport path through a vessel into which the treating fluid (e.g. developer, fixer or washing liquid, mist or gas) is admitted. The surface is provided with openings which are under suction so that a pressure differential is applied across a sheet carried along the surface to retain the sheet thereon without pressure members overlying the emulsion or sensitive side of the sheets. A drying chamber downstream of the fluid-treatment vessels circulates air into contact with the photographic paper or film, the air being dehumidified by a cooler in the circulating path. A counter responsive to the width and length of the photographic material measures the area treated.

States tet n91 Huber et a1.

[73] Assignee: Firma Autopan Heimerdinger &

Stabler GHG, Oberaichen/Wurtt., Germany 22 Filed: Apr. 5, 1973 21 Appl.No.: 348,188

[30] Foreign Application Priority Data Apr. 7, 1972 Germany 167711 Apr.28, 1972 Germany 162266 July 21, 1972 Germany 357604 Sept. 8, 1972Germany 440717 [52] U.S. Cl 354/324, 118/423, 118/429 [51] Int. Cl. .LG03d 3/02 [58]- Field of Search 95/94 R, 94 G, 89 R, 89 A, 95/93;118/423, 426, 429

[56] References Cited UNITED STATES PATENTS 3,311,039 3/1967 Lucas 95/94R nmwt [451 Jan. 14,1975

1/1968 Layne 95/94 R Primary Examiner--Richard L. Moses Attorney, Agent,or Firm-Karl F. Ross; Herbert Dubno [5 7] ABSTRACT An apparatus for thetreatment of sheet material, especially photographic sheets, comprises amultiplicity of surfaces or a single surface movable in a transportdirection and defining a transport path through a vessel into which thetreating fluid (e.g. developer, fixer or washing liquid, mist or gas) isadmitted. The surface is provided with openings which are under suctionso that a pressure differentialis applied across a sheet carried alongthe surface to retain the sheet thereon without pressure membersoverlying the emulsion or sensitive side of the sheets. A drying chamberdownstream of the fluid-treatment vessels circulates air into contactwith the photographic paper or film, the air being dehumidified by acooler in the circulating path. A counter responsive to the width andlength of the photographic material measures the area treated.

23 Claims, 16 Drawing Figures PMENFEIID 3.860844 SHEET 5 or 8 l5 5? ll53 PATENTED JAN 1 M975 SHEET 6 [IF 8 v av ww A, Y W 6.

PATENTED 1 W5 7 3'. 860 944 SHEET 8 (IF 8 APPARATUS FOR THE FLUIDTREATMENT OF PHOTOGRAPI'IIC SHEET MATERIAL WHEREIN THE LATTER IS PASSEDALONG AN ARRAY OF ROLLERS FIELD OF THE INVENTION BACKGROUND OF THEINVENTION Large-scale development of photographic papers or filmrequires subjecting at least the sensitive or emulsion side of thephotographic sheet material-to various fluids which may be in a liquidstate or in a gaseous state. The developing process may requiretreatment of the sheet material with one or more developer solutions orgases, one or more stop baths terminating the developing process, one ormore fixing baths in which the photo-sensitive component of theemulsion, not affected by exposure or development, is removed to leavethe image and various washing solutions between the chemical-treatmentstages. The treatment may also include a washing step in which thephotographic sheet material is treated with water until traces of thefixer are eliminated and for applying finishing chemicals to the sheetmaterial. Thereupon the sheet material is subjected to a drying step inwhich the treatment fluid may be heated air. In each of theaforementioned states, the emulsion side of the photographic sheetmaterial must be contacted with'a fluid in the liquid and/or gaseousphase.

In modern photographic processes, it is required to handle sheetmaterial at a high rate with a minimum of manipulation and a maximum ofautomatic control. To this end, it has been proposed to providetreatment vessels in which an endless-band conveyor forms a trans portpath against which the nonsensitive back or reverse face of thephotographic sheet is held, e.g. by a pressure band engaging theemulsion-carrying surface of the sheet. The transport bands may conveythe sheet material through the vessel or tanks in which the sheetmaterial is treated with a liquid.

A significant disadvantage of this system is the covering of a portionof the emulsion by the pressure band which holds the sheet against thetransport band. Since effective photographic development and treatmentrequires that all portions of the emulsion receive the same exposure tothe treating fluid, this system is inherently defective.

It has been proposed to alleviate this problem by subdividing thepressure band into a multiplicity of spacedapart strip-like belts whichpermit access of the fluid to the emulsion surface between the stripscovered by the band. It has also been proposed to stagger the bandssuccessively encountered by the sheet material to eliminate the stripingeffect which might otherwise occur.

In practice, none of these techniques has been found to be fullysatisfactory or free from the difficulty mentioned, namely, theirregular, nonuniform or discontinuous nature of the treating process.It may be mentioned in passing that even the reduction of the width ofthe strip-like bands spaced across the emulsion face of the sheet doesnot solve the problem since the reduction in the surface area of thepressure band or bands retaining the photographic sheet against thetransport band increases the tendency toward slippage and anunsatisfactory advance of the photographic sheets.

OBJECTS OF THE INVENTION It is the principal object of the presentinvention to provide an improved apparatus, for the treatment of sheetmaterial and especially photographic sheets, which has a high operatingrate, is of relatively low cost and is free from the disadvantagesenumerated earlier.

Another object of the invention is to provide an improved apparatus forthe purposes described which permits uniform access-"of a treating fluidto a sensitive surface of the sheet materials without the difficultiesencountered heretofore when pressing bands were employed.

Still another object of the invention is to provide an improved systemfor treating photographic sheet material whereby the aforementioneddisadvantages are obviated.

SUMMARY OE THE INVENTION These objects and others which will becomeapparent hereinafter are obtained, in accordance with the presentinvention, with an apparatus for the treatment of photographic sheetmaterials which comprises at least one displaceable transport surfacedefining a transport path through a treatment vessel and driven in thedirection of travel of the photographic sheet material along this path,the surface being provided with openings which are connected to asuction source so that a pressure differential is applied across thesheet material overlying this surface favoring retention of thesensitive or back face of the sheet against the surface. The sensitiveor emulsion face of the sheet is thereby exposed to the fluid and accessof the fluid to the sensitive face is not obstructed at least over amajor portion of this path.

The term photographic sheet material and terms of similar import areintended to refer to individual sheets of photographic paper which maybe exposed in contact with a negative or by a light beam trained thereonthrough a negative, to photo-sensitive materials exposed to other formsof electronic energy and developable by treatment, to photographic filmsor negative sheets and the like, and to photo-sensitive papers used forreproduction of a-master or an image and requiring development bycontact with a fluid.

According to a feature of the invention, the transport surface isconstituted by the peripheries of a plurality of tubular transportrollers which are journaled in a frame and are spaced apart along thetransport path with axes parallel to one another and to the plane of thephotographic sheet materials but orthogonal to the transport direction.Means is provided for rotating these rollers in the same sense. Thecylindrical rollers are formed with radial bores which communicate withthe cylindrical interior, the latter being connected via a pipe orconduit system or the liketo the suction side of a pump(fluid-displacement means) adapted to displace the treating liquid orgas through the vessels. The pressure side of the pump may be connectedto a feed duct of the vessel whereby the treating fluid is returned tothe latter.

As the treating fluid (liquid or gas) is drawn by a pump or blower fromthe transport rollers (or, more generally, from behind the aperturedtransport surface), a pressure differential is applied at the surfacethereof at each of the radial bores and, since a large number of boresmay be provided, the treating medium may circulate through the transportrollers without significant resistance. As the photographic sheetmaterial is passed onto the surface of the rollers is covers thera' dialbores therein and the resulting pressure differential retains thephotographic sheet material against the roller surface. Around the edgesof the sheet, the treat ment medium may continue to flow into the boresof the rollers.

When a treating liquid is used it is advantageous to increase the forcewith which the sheet is held against the transport surface by providingan increased fluid pressure against the sheet at its emulsion orsensitive side. The pressure differential, of course, increases as thelevel of treatment liquid in the duct system falls with increasingobstruction of the ports of the rollers as the sheet covers increasinglygreater portions of the surface. Thus the sheet material is retainedagainst the rollers without a pressing band or the like.

The transport rollers are driven by endless drive members, e.g. cables,belts or chains and, to achieve a uniform flow of the treating medium tothe duct system', it has been found to be advantageous to subdivide thehollow interior of the transport rollers with parti- I tions separatingdiscs, studs or plugs into the chambers of equal sizes.

Instead of the rotating transport rollers, we can provide between thevertical columns a pair of vertically spaced horizontal deflectionrollers about which passes a transport band covering substantially theentire length of each of these rollers and spanning the entire width ofthe chamber formed by the treatment vessel. The transport bandisprovided with openings under a pressure less than that in the chamberso that the uncoated or insensitive surface of the sheet is drawn by thepressure differential against the band and the treatment medium has freeaccess to the emulsion or photosensitive surface. Here again no pressingband is required and the full emulsion face of the sheet is in contactwith the treatment medium.

The transport band can be formed by a plurality of parallel endless bandportions or strip-like belts bridging a pair of common rollers orrespective rollers having a common axis of rotation. These individualband members define the openings of the transport band between them.

To prevent the inwardly directed forces which are transmitted from thesheet materials to the belt or band from urging the oppositely movingpasses thereof together, we can provide one or more supporting surfaces,e.g. rollers journaled in the support frame for the transport device orperforated or tubular supports through which the fluid medium iswithdrawn. According to a preferred construction of the mechanism of thepresent invention, thetransport device comprises a support frame orstructure having a pair of uprights which may constitute the ductscommunicating with the space behind the open-work surface against whichthe sheet material is pressed by the pressure differential. The tubularuprights may then be connected to the common suction or intake line(intake side) of a pump whose discharge or outlet line (discharge side)communicates with chambers or compartments outwardly of the photographicsheet material carrying the roller journal and extending the full heightand width of the treatment cell or vessel, the walls or plates beingprovided with ports which communicate with the space behind theopen-work surface. When the surface is composed in part by perforatedrollers or by bands passing over such perforated rollers or stationarytubes, the interiors of the rollers may communicate via theaforementioned ports with the ducts formed by the uprights. The interiorof each perforated roller, moreover, can be provided with plugsor otherpartition means subdividing the roller into two portions each of whichcommunicates through the wall or plate with a respective duct. Thisensures uniformity of suction across the length of the rollers. Ofcourse, the suction force may be applied by stationary perforatedsurfaces underlying the band or across which the photographic sheetmaterial is caused to move by rotatedor otherwise displaced surfaces.The stationary surfaces may also be placed under suction at their sidesturned away from the sheet material to draw the latter against thesurfaces. One roller may be displaced relative to the other to tensionthe band.

An important embodiment of the invention comprises an array of mutuallyparallel but vertically spaced horizontal rollers, each of which isperforated (i.e. provided with radial'bores), mounted upon respectivetubular sleeves projecting inwardly from the partitions or plates. Thesleeves may pass through the aforementioned openings in these plates tocommunicate with ducts on the opposite sides thereof. Each tubularroller thus is free to rotate upon a pair of sleeves forming the journalof the roll. Advantageously, the'end portions of each roller are formedto accommodate a driving means coupling the, rollers to a common drivesource.

It has been found to be advantageous to provide above the array ofrollers at each treatment vessel, a feed roller along which the sheetmaterial is directed downwardly into the vessel and'into engagement withsuccessive displacement rollers, all rotating in the same sense. Thefeed roller may be provided with a worm wheel which, when the framecarrying. the rollers is lowered into the upwardly open vessel or cell,rests upon and engages the worm of amotor disposed externally of thecell casing. A flexible force-transmission member, e.g. a cable, belt orchain, passes around the end formations of the roller to drive thelatter in a single sense. Thus, on one side of the array of rollers, thesurfaces move downwardly to entrain the photographic sheet material intothe cell while, on the opposite side of the array, the surface moveupwardly to carry the sheet material out of the cell and, if desired,into the next treatment vessel. The drive means preferably includes atleast one endless member passing around each uppermost roller of thearray and around the next lowermost roller so that the roller of thearray are coupled together for joint rotation in a common sense. When achain is used as an endlessmember, the end formations of j the rollersmay be sprocket wheels whereas the end formations may be grooved toaccommodate a belt when the latter constitutes the torquetransmissionmeans.

We have also found it to be advantageous to constitute the frameworkfrom a plurality of plates including the two plates mentioned earlier,which lie in vertical planes and flank all sides of the roller arrayover the full height of this array. These walls may be provided withopenings through which the treating fluid can be passed. The walls thuslie ahead of the mouth of the outlet duct from the pressure side of thepump communicating with the compartment of the vessel.

The suction effect of the pump and the rate at which the treating mediumis fed to the vessel may be controlled by a valve in one of the linesconnecting the pump to the vessel, preferably the fluid feed line.

It has been found to be advantageous to provide a number of such vesselsin series for the treatment of the photographic sheet materials withdifferent liquids. It has been pointed out earlier that these liquidsmay include one or more developers, one or more rinsing or washingliquids, stop bath and one or more foxer solutions, each liquid ortreating fluid being applied to the sheet in a respective vessel so asto prevent intermixture. In this case, the serially arranged vessels areplaced in a row with the upstream side or wall of each vessel contactingthe downstream side of an adjoining vessel, a deviating device beingprovided between each pair of vessels to deflect the rinsing sheet of anupstream vessel downwardly into the next downstream vessel for passagetherethrough by the transport means of this latter vessel. The deviatingdevice preferably comprises an array of rollers constituting a rollerconveyor. The axes of these rollers lie along an arc extending from alocation directly above the uppermost roller of one vertical array to alocation directly above the uppermost roller of the next array, the axesbeing spaced apart by a distance less than the diameter of theindividual rollers but greater than the radius thereof. The latterrollers may, moreover, be axially spaced along the respective axes sothat they interdigitate with the rollers on the upstream and downstreamsides thereof (i.e. the rollers of successive axes along the sheet pathare staggered with respect to one another). It has also been found to beadvantageous to provide at the bottom of each array of tubular transportrollers or conveyor band system in accordance with the presentinvention, a deflecting means which may include a pressing bandpassing'around a pair of rollers whose axes lie -in a plane in orsomewhat above the lowermost roller of the array. The return pass ofthis deflecting device defines withthe first mentioned rollers atriangle. The rollers of'the deflection device may have axes parallel tothose of the transport array and serve to sandwich the sheet materialbetween the transport surface (band or roller) and the deflection bandso that the sheet wraps around the lowermost roller of the transportdevice as it rises along the opposite side of the rollers of thetransport array.

Either the roller conveyor or the conveyor-belt deflector and preferablyboth may extend over an arc of substantially 180.

According to another feature of this invention, the battery of treatmentvessel terminates in a drying apparatus which is also provided withmeans for conducting the photographic sheet material through a treatmentchamber in which it is subjected to a fluid, e.g. drying air, which maybe at a higher temperature than ambient. The drying apparatus isprovided with a plurality of transport rollers about which a transportband or belt passes in a closed path. The belt is provided with openingsthrough which circulated air can pass into a space within the zonedefined by the belt. In this embodiment as well, the zone enclosed bythe belt is evacuated by an air-circulation device (e.g. a blower) whosesuction or intake side is connected to this zone and whose outlet opensor discharge side into the zone surrounding the belt. I I

To remove moisture from the circulated air. we provide in thecirculation path a cooling device which is maintained at a temperaturebelow the dewpoint ofcirculated air so that moisture picked up by theair upon contact with the photographic material is condensed at thecooler. The latter may be a heat exchanger and the precipitated watermay be collected and, in order to minimize the operating costs of thedevice, can be returned as a diluting fluid for the chemicals used totreat the photographic material in the battery of vessels previouslydescribed, or to a rinsing vessel. It has also been found to beadvantageous to operate the heat exchanger with a sheet-treating liquidand thus the heat exchanger is provided in the line feeding water to anyof the treating vessels. When control of the temperature of the waterdelivered to one of the treating vessels is required, we may provide amixing chamber downstream of the heat exchanger in the water-supply lineand a valve for controlling mixing of a portion of the condensed waterwith the cooled water delivered to the vessels. A mixing valve may alsobe provided for bypassing a part of the cold water past the heatexchanger and to the mixing chamber. The condensed water can becollected in a tray or trough and led away via a discharge line ifdesired.

It has also been found to be advantageous to provide counting meansalong the path of the sheet material, preferably in the form of switchesactuated by the leading edge of each sheet. A register may indicate thecount and alert the operator to the depletion of any of the chemicalsused or the completion of processing of a predetermined sheet area. i

The counting device preferably comprises an array of balls which arefree to move in windows of a plate disposed above the path of the sheetmaterial and displaced upwardly by the leading edge of the sheet. Asensitive switch is actuated by each ball and constitutes an input to acontrol device. Advantageously the switches are provided in circuit withrespective magnetic switches which can be arranged in a crownconfiguration with a common return conductor in circuit with a counter.The magnetic switches are operated in succession by a disk carrying amagnet once during each revolution of this disk.

DESCRIPTION OF THE DRAWING The above and other objects, features andadvantages of the present invention will become more readily apparentfrom the following description, reference being made to the accompanyingdrawing in which:

FIG. 1 is a vertical elevational view, partly in diagrammatic form,illustrating the apparatus according to the invention;

FIG. 2 is a plan view, drawn to an enlarged scale, of one cell or vesselof the apparatus of FIG. 1;

FIG. 3 is a cross-sectional view taken along the line III III of FIG. 2;

FIG. '4 is a side-elevational view, partly broken away, of a transportsystem according to an embodiment of the invention; I

FIG. 5 is a detailview, partly in axial section, showing a portion ofthe device of FIG. 4;

FIG. 6 is a vertical elevational view, partly broken away, of anotherembodiment of the transport means according to the invention;

FIG. 7 is a section taken along line VII VII of FIG.

FIG. 8 is a vertical section through an embodiment of the inventionhaving upper and lower deflectors;

' FIG. 9 is a fragmentary sectional view illustrating another upperdeflector;

FIG. is a view taken in the direction of arrow A (FIGS. 8 and'9);

FIG. 11 is a vertical section through a drying chamber according totheinvention;

FIG. 12 is a vertical cross-sectional view through a treatment apparatusprovided with another drying means according to the present invention;

FIG. 13 is a vertical section of the drying chamber of anotherembodiment of the apparatus;

' FIG. 14 is a somewhat diagrammatic elevational view, partly brokenaway,'of a sheet-detecting arrangement according to the invention;

FIG. is a view taken generally in the direction of arrow B in FIG. 14;and

FIG. 16 isa side-elevational view of a disk arrange ment with a magneticswitching according to the invention.

SPECIFIC DESCRIPTION FIG. 1 shows, somewhatdiagrammatically, anapparatus for the development of photographic paper or into theapparatus, the means comprising a pair of downwardly curved guide platestogether defined a feed slot 3 into which the leading edge of the sheet4 may be introduced into the direction of arrow 5. As the sheet is fedto the first cell, it is entrained downwardly through a treating liquid(developer) or in juxtaposition with nozzles admitting a treating gas bya transport device represented generally at 6 and constituted as setforth in connection withany of the subsequent Figures. As the sheetrises along the transport device 6, it is diverted via a deflectingdevice 7 downwardly into the next vessel 1. The process continues -untilthe roller conveyor 8 deposits the sheet material onto a belt conveyor 9which carries the sheet into the drying device. Deflecting device 7, ofcourse, is also a roller conveyor.

FIGS. 2 6 illustrated various transport systems whereby the sheetmaterial is passed downwardly through the narrow vessels or cells andthence upwardly to emerge from the open top of the vessel for.deflection to the next treating stage.

The transport means within each cell may comprise two vertical beams oruprights 10 carrying a frame 18 etc. at its upper end received centrallybetween the two opposite walls 44 of the cell.

A plurality of vertically spaced mutually parallel tube-like hollowrollers 12 are journaled on the uprights 10 below an inner feed roller11. Externally of the vessel 1, there is provided a motor 13 whose, wormengages a worm wheel of a step-down partition 14 connected to theuppermost roller 11 by a shaft 15 (FIG. 4).

The rollers 12 are driven by belts l6 and 17 connecting the upper roller11 to the topmost roller'12 and each roller .12 with the next lowerroller. To this end, the rollers 12 are formed with cylindrical bossesat their opposite ends having circumferential grooves receiving thebelts 16 and 17. Of course, a chain drive may also be used in which casethese bosses would be formed as sprocket wheels. All the rollers 11and.l2 are thus driven in common and in thesame sense by the shaft 15.

The supporting uprights 10 carry the frame structure 18 etc. which actsas a confinement (see especially FIGS. 2 and 4). The structure comprisesa pair of vertical plates 18 extending the full height of the vessel 1and the uprights10 may be constituted as ducts 19 which terminate inpipe fittings 20. As can be seen especially from FIG. 5, the spacing ofthe transport rollers 12 corresponds to the spacing of bores 21 in theplates 18 which receive the small-diameter portions of respectivetubular sleeves 22 upon which the transport rollers 12 are rotatablymounted. The resulting journal is represented at 23.

Each of the transport rollers 12 is provided with bores 24 communicatingwith the interior'of the rollers, the latter being represented at 25 andbeing subdivided by a plug 26 into two compartments 27. Each'of thecompartments 27 is connected to a respective sleeve 23 and the bore 21ofthe wall 18 with the respective ducts 19. r

The entire assembly 6 is rigid and can be lifted upwardly out of andinserted downwardly into the upwardly open vessel 1 whereby the outeredges of each partition plate enter respective vertical grooves 28 ofledges 29 affixed to the inner walls 44 of the vessel 1. At the sametime the pipe fittings 20 at the bottom ends of the ducts 19 (FIG. 4)pass'through the floor 30 ofthe vessel 1 (see FIG. 3) and connect to themating pipe fittings 31. The latter communicate with a pipe network 32connected to a pump 33. Just as the fittings 20 engage tightly into thefittings 31, the worm wheel 14 of the roller comes to rest in meshingrelationship with the worm.

As can be seen from FIGS. 2, 3 and 7, between the supports 29 andflanking the array of transport rollers 12, there are provided a pair ofpartitions or walls 34 which slide downwardly in respective guidegrooves 35 of the support 29. The partitions or walls 34 are formed withholes 36 through which the treating fluid can be introduced into thespace 37 enclosed by the four vertical plates 18 and 34.

To permit the pump 33 to circulate the treating fluid back into thevessel 1, a supply line 38 (FIG. 3) is-provided whose horizontally bentend 39 passes through the wall 40 of the vessel and is formed at itsmouth with a deflection plate 41 to divert the flow of fluid upwardlyand downwardly as represented by the arrows 43. A valve 42 is providedin line 38 and thereby controls the discharge rate of pump 33 and,indirectly, the suction developed within the space enclosed by theperforated transport surfaces.

When photographic sheet material is fed into the first vessel 1 over thefeed roller 11 and the pump 33 is energized, the treating fluid is drawnfrom the space 37 enclosed by the vertical walls 18 and 34 via thetransport rollers 12 and the ducts 19, through the conduit 32 and to thepump 33. The fluid is then returnedvia the feed duct 38 to the vessel 1whereby the treating fluid is deflected upwardly and downwardly by thebaffle 41 as represented by the arrows 43. From the space around theenclosure 18, 34, the liquid flows through the perforations 36 into thespace 37 to enclose the circulation path.

The sheet material introduced into the space 37 in the direction ofarrow 5 (FIG. 1) and arrow 47 (FIG. 3) is entrained downwardly by thesuction at the uppermost transport roller 12, a portion of the radialbores 24 of which are covered. The sheets thus lie flush against thesurfaces of the rollers 12 and are held by the pressure differentialapplied thereacross between the radial bores 24 and the remainder of thechamber 37 with a force which is equal to the product of the totalcross-sectional area of all the blocked bores and thus pressuredifferential. The rollers 12 at the side onto which the sheets initiallypass move in the downward direction entraining the sheet materialsimilarly (arroS in FIG. 8). This force is such that the sheets are heldonly with enough pressure as to keep them from moving relative to thesurface of the roller but not sufficient to cause the leading edge ofthe sheet to bend around the roller. Alternatively, the belts 17 mayunderlie the outer edges of the sheet material so that from roller toroller the sheet material passes without deflection in spite of rotationof the apertured surface. In other words the sheet material is merelyentrained by the rollers by generally tangential contact and without atendency of the sheet material to bend to conform with the rollersurface.

The downward movement of thesheet material continues untilthe lowermostroller 12 is reached, whereupon the sheet material is deflected through180 and rises in contact with the diametrically opposite sides of therollers 12. Since the movement of the sheet material along the rollersprogressively blocks more and more radial bores 24, the liquid must bedrawn through fewer and fewer bores 24. This has the effect of reducingthe level ofliquid in the duct system 19/32 with respect to the level ofliquid in chamber 37, thereby reinforcing the pressure differentialapplied to the sheet material and retaining it against the rollers.

Control of the flow rate of the liquid via valve 42 in the supply line38 permits regulation of the contact pressure applied to the sheetmaterial. This control is important since the degree to which the ports24 are covered by the sheet material is a function of the size andnature thereof.

FIG. 6 shows a modification of the system according to the presentinvention in which, in place of the rotatable rollers 12, stationarysuction tubes 48 and nonperforated suction tubes 49 are provided, thelatter extending only limitedly from the opposite walls 18 of thesupport structure. The lowest suction tube 50 is provided with freelyrotatable rings 51 around which a perforated belt 52 passes, the belt 52passing over the infeed roller 1 l. The perforations 53 of the band 52permit the flow of fluid through this band into the space 54 enclosedthereby, this space being connected to a suction source as described forthe chamber 37.

The operation of the pump includes a flow of treating liquid from thespace 54 defined by the band 52 and the lateral walls 18 through theperforations 55 of the stationary suction tubes 48 and through the mouth56 of the nonperforated suction tubes 49 into the ducts 19 forming theuprights 10. The liquid is then carried by a duct system similar to thatshown at 31 and 32 to the intake side of pump 33 and is returned via thefeed duct 38 to a nozzle and baffle arrangement 41 communicating withthe space around the enclosure 54. In this embodiment, as in theembodiment of FIG. 4, the suction tubes 48 and 50 are subdivided byplugs 57 into respective axial compartments communicating with therespective ducts 19.

In general, the system of FIG. 6 operates similarly to that of FIGS. 2and 3 in that a photographic sheet brought into contact with theperforated band 52 will be entrained in the direction of arrow 47 andwill contact, with its uncoated side, the outer surface of the band 52.A portion of the perforations 53 of the band 52 will be obstructed and,as a result, a pressure differential is developed which presses theuncoated surface of the sheet material against the band. The liquid towhich the sheet material carried by the band is exposed, provides thenecessary treatment free from any interference by a surface masking theemulsion face.

FIGS. 8 and 9 show in section the transport device of a vessel 1 whichis provided with means for deflecting the emerging sheet into the nextvessel (FIG. 1) and for facilitating a transition between the downwardmovement of the sheet material and upward'displacement thereof at thebottom of the vessel. The deflection means 59 at the bottom of thevessel comprises three deflection rollers. The deflection .rollers 60flank the array of transport rollers 12 and the band 52 and have axes ofrotating lying in a horizontal plane above the axis of the lowermostroller 12 so that a deflection band 62, passing around the rollers 60,is slung underneath the region at which the band 52 is deflected fromits downward stretch into its upper stretch. A third deflection roller61 defines a triangle with roller and may have its axis lying in acommon vertical plane with the axes of the rollers 12. The roller 61lies beneath the lowermost roller 12. The deflection band 62 has a bightparalleling the band 52' through 180 and holds the sheet materialthereagainst as it makes its transition from the downward movement tothe upward movement. Thereafter, the band 62 is deflected away from thetransport band 52 so that treatment of an uncovered sensitive surface ofthe photographic sheet may continue. It will be appreciated that, inFIGS. 8 and 9, the band 62 has been shown to cooperate with a perforatedband 52 which passes over perforated rollers 12. It may also be usedwith perforated rollers alone and with a perforated band passing overrollers which are not perforated. The band may also pass over stationarysuction tubes provided with suction apertures distributed over theirlengths or having only an axialsuction inlet at the mouth of the pipe.In general, therefore, we prefer to sling a deflector band under theperforated or open-work suction surfaces no matter how the latter areconstituted.

To deflect the photographic sheet material from one vessel to the next(FIG. 1), the roller-conveyor deflectors 7 are provided. Each of theseconveyors comprise an arc-shaped array 65 of rollers having individualballbearing wheels v66 axially spaced apart upon shafts 67 (if thelatter are not driven). This structure is best seen in FIGS. 8 10. Theare (FIG. 8) may extend from the topmost roller of the array ofperforated rollers or from the top of the conveyor band system of onevessel to the top of the array of rollers or conveyor band of the thusthe arc of the roller conveyor must have a length which is less than thelength of the sheet in the direction of movement thereof. Of course, thewheels may be driven with a peripheral speed equal to the conveyor orperforated-surface speed as required.

As will also be apparent from FIGS. 8 and 10, each row of wheels carriedby a common shaft 67 or 68 interdigitates with a pair of adjacent rowshaving a spacing which is less than the wheel diameter but greater thanthe wheel radius. The sheet 4 (FIG. 8) is thus'engaged by the wheelalong its nonsensitive or backing surface and is deflected downwardlysuch that its backing surface is entrained by the perforated surface ofthe next array of rollers or conveyor band. The wheels lie tangent to acircle substantially of the diameter a which corresponds to the spacingof the successive bands from one another, less twice the thickness ofthe sheet which is processed.

In FIG. 9 we have shown another deflector system wherein, however, the.roller conveyor does not lie along a circular are through 180 betweenthe perforated conveyor bands of adjoining cells, vessels orcompartments. The roller conveyor 70 here forms a highly v flattened arewhich nevertheless deflects the sheet material although we prefer toprovide a row of wheels 66 upon. a shaft 71 engageable with the emulsionface of the sheet material to provide greater security insofar as 7advance of the sheet from one vessel to the other is concerned.

The apparatus according to the present invention is provided, at the endof the battery of cells or vessels 1,

with a drying installation represented generally at 2. In

this device, as in each cell, the sheet material is sub-' jected totreatment with a fluid (circulating air in the case of the dryer) and isheld against a transport surface by a fluid-pressure differential.

FIG. 12 shows this arrangement in somewhat greater detail, only a singlecell 1 being illustrated ahead of the drying chamber although, undernormal conditions, a row of such cells is provided.

The drying device comprises a chamber 72 having an inlet opening 73 atwhich a pair of feed rollers 74 is provided. Between the transportdevice 6 of the last vessel 1 and the inlet 73 to chamber 72, there isprovided an arcuate roller conveyor 8, which may be identical in allrespects to the roller conveyors described in connection with FIGS. 8and 10. The roller conveyor 8 deflects the sheet material as representedby the arrow 77 onto an endless conveyor 9 passing about horizontallyspaced rollers 75, 76 which leads the sheet material into the nipbetween the transport rollers 74. A deflection plate behind these latterrollers directs the sheet downwardly.

Between the vertical side walls 78 (all of the vertical walls beingdesignated 78) of the drying chamber 72, there are provided transportrollers '79 which are spaced around. a closed path and serve to supportan endless transport belt 80, the latter being perforated as describedfor the band 52. At a distance b from the bight 81 or U-shaped stretchof this perforated band 12 80, a U-shaped partition 82 is disposed. Thepartition 82 is formed with perforations 84 through which air can beadmitted into the space surrounding the band 80 as represented bythearrow 83.

At the rear wall 78, within the zone surrounded by the rollers 79 andtheband 80, there are provided air outlet openings 85 which areconnected by ducts and a blower to the air-inlet slits 86 in the walls79 between the partition 82 and the outer wall 72. The air emerging fromthese slots can thus return into contact with the sheet materialthrough, the openings 84.'lt.will be apparent, therefore, that the airdisplaced by a blower not illustrated in FIG. 11, is drawn from thechamber 88 surrounded by the band 80, thereby retaining the sheets 4against this band, and is returned to the space 87 around the band anddirected against the sheet material thereon to further support the sheetmaterial on its transport surface. At the upper end of the. Path of theband 80 in the drying chamber it is deflected sharply to the left (FIG.11) and, because of the stiffness of the photographic sheet material,the leading edge thereof does not follow the band but instead issuesfrom the device through a slot 90 as represented by the arrow 91.-

The air circulating past the sheet material 4 picks up moisturetherefrom and suffers an increase in its relative humidity, To removethis moisture, we provide in I a space 88 surrounded by the band 80, acooling device 92 having at its basea water-collection through 93 fromwhich the collected water can be led by a duct 94 to one of the vessels1 as replacement water. The cooler 92 lowers the temperature of. thecirculated air below its dewpoint and may be provided with a blower (notshown) for circulating air in the space 88 into heat-exchangingrelationship with the surfaces of the cooler. The dehumidified aircontinues it circulation and may be passed through a heating device towarm it to its original temperature or a temperature above ambient. Theheat-exchange fluid fed to the cooler 92 may be cold water which isheated during the drying process and can be led to one of the vessels 1as previously described.

FIGS. 12 and 13 illustrate another embodiment of the invention in whichthe drying arrangement 95 serves to dry a continuous film 96 passingabout rollers 111. The apparatus which terminates in the drying deviceof FIG. 12 comprises six treating vessels 97 102 which are traversed insuccession by a photographic film strip 96 passing over deflectingrollers 103 in the direction of the arrows 104. I i

In tanks 97, 99 and 101 of the apparatus, the film is treated withdeveloping liquids, stop bath and fixer, respectively, while the tanks98, and 102 are provided with rinsing water delivered by a line 106 andsupplied in the direction of arrow 107. Inother words, the film iswashed, after each chemical treatment, by fresh water delivered .to thetanks or vessels 98, 100 and 102 downstream from each of the treatmentvessels.

Immediately downstream of the last treatment vessel 102, there isprovided a drying station which has been represented at 95 in FIGS. 12and 13-and is provided with a drying unit 109 and a chamber 110 in whichthe film is treated with the drying air. The film 96 is passed in azig-zag pattern about rollers 111 in the chamber 110 and moves generallyin the direction of the arrow 112.

The air-circulation unit 102 comprises a radial blower 113 having anelectrical resistance heating element 115 spanning its outlet opening114. The air from this blower is trained in the direction of arrow 116upon the film carried along the path defined by the rollers 111.

Below the radial blower 113, there is provided a cooling unit 118 whichis formed with heat-exchange ribs or fins 117 and through which coldfresh water is fed via the fresh-water feed line 106. Since the freshwater traverses the cooler 118 before it enters the washing tanks 98,100, 102, the water is somewhat warmed while the air passing over thisheat exchanger and the fins is cooled, thereby condensing moisture whichis collected in a trough 123 (FIGS. 12 and 13).

The heating element 115 warms the air before it returns to the dryingchamber 110.

In operation, the intake side of blower 113 draws air upwardly in thedirection of arrow 125 within the compartment 122 set off by a partition120 from the chamber 110. Air is induced to flow into the compartment122 through an opening 121 at the bottom of this partition 120 and thusa downward flow of air 119 is provided within the chamber 110.

As the moisture-lated air passed over the cooling coil 126 of FIG. 13 orthe fins 117 of FIG. 12, it encounters surfaces at a temperature belowthe dewpoint of the air and condenses moisture thereon, the waterdroplets being collected in the trough 123. The cooled air, carrying areduced proportion of moisture, is then drawn into the blower 113 and isforced through the outlet 114 over the resistance-heating elements 115where it is rewarmed to increas its moisture-carrying capacity. Thewarmed air then flows over the film 96 to dry the latter and pick upadditional moisture. Of course, the heat delivered by elements 115 tothe air is transmitted in part to the fresh water fed to the chemicaltreatment tanks and no other means is required for heating this water.The condensed water from trough 123 is carried off by a line 124 and maybe fed to the tanks as part of the water making up the chemicalsolutions or constituting the washing fluid.

In FIG. 13 a drying arrangement has been illustrated in which a coolingloop 126 is provided as the heat exchanger. Of course, the cooling loopmay be charged with water to be fed to the treatment tanks or may simplybe part of a refrigerator cycle using the refrigerant such as FREON. Inthe system of either FIG. 12 or FIG. 13, a bypass may be provided acrossthe heat exchanger as represented at 106a for mixing at a chamber 106b aquantity of cold water with the warm water from the heat exchanger. Apump 106C may be used to feed collected water into this mixing chamberas well (see FIG. 12).

In FIGS. 14 16 we show an apparatus, according to the invention, whichincludes a counter disposed at the inlet 3 to the system and responsiveto the presence of the photographic sheet for indicating the treatedarea thereof. The system operates with a row of sensors across the pathof the sheets, the number of sensors operated by the sheet being afunction of the width thereof. All of the operative sensors are scannedperiodically to a counter or register so that the pulse count orregistered indication represents the area of the sheet which has beentreated. For example, with each periodic scan, each sensor operatedacross the width of the sheet will trigger the register only for aduration representing the length of the sheet and only those sensorsacross the width of the sheet will be operated.

As can be seen from FIG. 14, there is provided in the region of the feedslot 3 a curved plate 128 which extends transversely to the feeddirection 5 and is provided with a row of circular openings eachreceiving a ball 130 which rests by its weight against the lower plate131 defining the inlet slot 3. Each ball 130 is provided with asensitive sheet 132 whose spring finger 133 likely biases the balldownwardly but is deflectible by slight movement of the ball to operatethe switch actuator 134. As the photographic sheet passes beneath therow of balls, only those balls across the width of the sheet are liftedto operate their sensitive switches 132. Each sensitive switch 132 isconnected in series with a current source 142 and a communicatingarrangement represented generally at 140. From the communicatingarrangement, all of the switches are returned via a counter 148 to theother terminal of the source. The commutating arrangement comprises adisk 137 upon which a crown of magnetically actuatable (reed) switchesare provided, each in series with a respective microswitch 132 and theline 141 connected via a conductor 143 to the counter 148. From FIG. 16,it will be apparent that the disk 137 is confronted by a rotating disk145 whose face 146 confronting the magnetic reed switch crown is formedwith a magnet 147 which operates each magnetic switch 138 once perrevolution of the disk 145. It will be noted further from FIG. 15 that anumber of photographic sheets 139 can be passed in parallel through theapparatus and that it is not necessary to align the leading edges ofthese sheets since the counter will respond to the product of the widthand length as noted. When the balls are spaced apart by 1 cm and thearray of magnetic switches is scanned once for every cm of advance ofthe sheets, the number registered by the counter will be the total areain cm As the magnet 147 sweeps past each reed switch 138 it closes thecontacts and, in the event the associated microswitch 132 is in a closedstate, causes a signal to register at the counter 148. If threemicroswtiches along the array are closed by a single photographic sheet,the actuation of the corresponding number of reed switches will providea respective number of counts. Of course, when the sheet has passed therow of balls, the microswitches previously actuated are released and nofurther counts register until the balls are again lifted. As aconsequence, the counter records the total area of the photographicsheets processed.

I claim:

1. An apparatus for the treatment of photographic materials, comprising:

a housing;

roller means defining a transport path for a photographic materialhaving a sensitive face and a reverse face;

means forming at least one open-work surface engageable with saidreverse face of the photographic material and displaceable to entrainsaid photographic material along said path;

means for treating said sensitive face with a fluid and includingfluid-displacement means having an intake side communicating with saidhousing on the side of said path opposite said sensitive face and adischarge side communicating with the interior of said surface outwardlyof the sensitive face of photographic material disposed thereon, saidmeans forming said surface being the surface of said roller means, saidroller means comprising a plurality of tubular rollers spaced apartalong said path and provided with radial bores opening at the surfacesof said rollers, said intake side of said fluiddisplacement meanscommunicating with the interiors of said rollers; and

a support frame receivable in said housing and having a pair of uprightscarrying said rollers, at least one of said uprights being hollow andforming a duct connecting the interiors of said rollers with said intakeside of said fluid-displacement means.

2. The apparatus defined in claim 1, further comprising drive meansincluding at least one flexible endless element passing about two ofsaid rollers for rotating same.

.3. The apparatus defined in claim 1, further comprising a pair ofupright lateral walls flanking said rollers and received in saidhousing, said walls being formed with bores and with cylindrical sleevesreceivable in said bores, said rollers being rotatably mounted on theexteriors of said sleeves and communicating therethrough with saidintake side of said fluid-displacement means.

4. The apparatus defined in claim 1 wherein said uprights are formedwith downwardly projecting tubular fittings receivable inupwardly opensockets formed at the bottom of said housing and communicating with saidintake side of said fluid-displacement means.

5. The apparatus defined in claim 1 wherein said rollers are eachsubdivided into two portions, each communicating with the interior of arespective hollow upright and connected thereby to said intake side ofsaidfluid-displacement means.

6. The apparatus defined in claim 1 wherein said means for treating saidsensitive face with said fluid includes a partition extendingsubstantially parallel to said path and defining a compartmentwithinsaid housing along a side of said partition opposite thatjuxtaposed with said path, said partition being perforated, and meansconnecting said discharge side of said fluiddisplacement means with saidcompartment.

7. The apparatus defined in claim 6 wherein said discharge side isprovided with an outlet opening into said compartment, said outlet beingformed with a baffle for deflecting fluid parallel to said partition.

8. The apparatus defined in claim 1 wherein said photographic materialis to be treated with a number of fluids, said apparatus comprising aplurality of vessels each having such a housing, roller means andsurface, said apparatus further comprising deflector means for divertingthe photographic material from one housing into the other housing, saiddeflector means including a roller conveyor disposed above the path ofsaid one housing and leading to the path of said other housing.

9. The apparatus defined in claim 8 wherein said roller conveyorcomprises a plurality of shafts lying along an are between said housing,and a plurality of axially spaced rollers mounted on each shaft with therollers of adjacent shafts in interdigitating relation.

10. An apparatus for the treatment of photographic material, comprising:

a housing;

roller means defining a transport path for a photographic materialhaving a sensitive face and a reverse face;

means forming at least one open-work surface engageable with saidreverse face of the photographic material and displaceable to entrainsaid photographic material along said path;

means for treating said sensitive face with a fluid and includingfluid-displacement means having an intake side communicating with saidhousing on the side of said path opposite said sensitive face and adischargeside communicating with the interior of said surface outwardlyof the sensitive face of photographic material disposed thereon, saidroller means including a pair of spaced-apart rollers and said surfacebeing defined by at least one conveyor band extending around saidrollers; and

means for displacing one of said rollers relative to the other totension said band. 11. The apparatus defined in claim wherein said bandis preforated.

12. An apparatus for the treatment of photographic materials,comprising:

a housing; roller means defining a transport path for a photographicmaterial having a sensitive face and a reverse face;

means'forming at least one open-work surface engagable with said reverseface of the photographic material and displaceable to entrain saidphotographic material along said path; means for treating said sensitiveface with a fluid and including fluid-displacement means having anintake side communicating with said housing on the side of said pathopposite said sensitive face and a discharge side communicating with theinterior of said surface outwardly of the sensitive face of photographicmaterial disposed thereon, said roller means including at least one pairof spaced-apart rollers and said surface being formed by an endlessperforated conveyor band extending around said rollers; and

stationary support members spaced apart along said path and engaged bysaid band, said support members opening into the space enclosed by saidband, said intake side of said fluid-displacement means communicatingwith said space through said members.

13. An apparatus for the treatment of photographic materials,comprising:

.a housing;

roller means defining a transport path for a photographic materialhaving a sensitive face and a reverse face;

means forming at least one open-work surface engageable with saidreverse face of the photographic material and displaceable to entrainsaid photographic material along said path;

means for treating said sensitive face with a fluid and rollers and saidsurface being formed by an endless perforated conveyor band extendingaround said' rollers; said rollers being spaced apart vertically in saidhousing, the lowermost roller being tubular; and

openings in said lowermost roller communicating with said intake side ofsaid fluid-displacement means, said lowermost rollers being providedwith axially spaced rings freely rotatable thereon and engaging saidband.

14. An apparatus for the treatment of photographic materials,comprising:

a housing;

roller means defining a transport path for a photographic materialhaving a sensitive face and a reverse face;

means forming at least one open-work surface en gageable with saidreverse face of the photographic material and displaceable to entrainsaid photographic material along said path;

means for treating said sensitive face with a fluid and includingfluid-displacement means having an intake side communicating wtih saidhousing on .the side of said path opposite said sensitive face and adischarge side communicating with the interior of said surface outwardlyof the sensitive face of photographic material disposed thereon;

a conduit connecting said discharge side of said fluiddisplacement meanswith the interior of said housing: and

a valve in said conduit for controlling the fluidpressure differentialacross photographic material on said surface.

15. The apparatus defined in claim 14 wherein said roller means includesa pair of rollers spaced apart along said path and said means formingsaid surface is at least one conveyor belt passing endlessly around saidrollers, said apparatus further comprising a pair of vertical lateralwallsflanking said belt and defining therewith a first chambersurrounding by said belt and a second chamber between said belt andwalls of said housing, at least one of said lateral walls being formedwith an opening communicating with said first chamber and connected tosaid intake side of said fluid-displacement device, one of said lateralwalls being formed with a slot extending parallel to said belt andopening into said second chamber while communicating with said discharge side of said fluid-displacement device.

16. The apparatus defined in claim 14 wherein said path has a downwardlyextending stretch and an upwardly extending stretch in said housing,said apparatus further comprising deflector means at the bottom of saidpathdiverting the photographic material from said downward stretch intosaid upward stretch, said deflector means comprising a pair of rollersflanking said path and a third roller disposed therebelow, and anendless deflector band passing around said rollers of said deflectingmeans for retaining said photographic material against said surfaceduring the transition from said downward stretch to said upward stretch.

17. An apparatus for the treatment of photographic materials,comprising:

a housing;

roller means defining a transport path for a photographic materialhaving a sensitive face and a reverse face;

means forming at least one open-work surface engageable with saidreverse face of the photographic material and displaceable to entrainsaid photographic material along said path;

means for treating said sensitive face with a fluid and includingfluid-displacement means having an intake side communicating with saidhousing on the side of said path opposite said sensitive face and adischarge side communicating with the interior of said surface outwardlyof the sensitive face of photographic material disposed thereon, saidhousing defining a drying chamber downstream of a system for thechemical treatment of photographic material, said drying chamber havinga blower for directing air against said photographic material on saidsurface and for drawing air from said housing beyond said surface;

cooling means in the path of air circulated by said blower fromcondensing water therefrom; and means for collecting the condensedwater.

18. The apparatus defined in claim 17 wherein said path is generallyU-shaped and said surface is a perforated band extending endlesslyaround said path, said cooling means being disposed within the spacesurrounded by said band.

19. The apparatus defined in claim 18, further comprising a perforatedpartition extending parallel to said path andclosely spaced therefrom,said blower'communicating with said housing between said partition andan outer housing wall, the total area of the perforations of saidpartitions being greater than the area of the perforations of said band.

20. The apparatus defined in claim 17 wherein said drying chamber isprovided downstream of a chamber for the liquid treatment of saidphotographic material with an aqueous solution, said apparatus furthercomprising means for passing water through said cooling means andthereupon into said treatment chamber.

21. The apparatus defined in claim 16 wherein said drying chamber isprovided downstream of a treatment chamber for contacting saidphotographic material with a liquid, further comprising means fordelivering condensed water from said cooling means to said treatmentchamber.

22. An apparatus for the treatment of photographic materials,comprising:

a housing;

roller means defining a transport path for a photographic materialhaving a sensitive face and a reverse face;

means forming at least one open-work surface engageable with saidreverse face of the photographic material and displaceable to entrainsaid photographic material along said path;

means for treating said sensitive face with a fluid and includingfluid-displacement means having an intake side communicating with saidhousing on the side of said path opposite said sensitive face and adischarge side communicating with the interior of said surface outwardlyof the sensitive face of photographic material disposed'thereon; meansdownstream of said housing for contacting said photographic materialwith a stream of drying air subsequent to its treatment with said fluid,the last-mentioned means including: a blower for the circulation of air,heating means at a discharge side of said blower for heating thecirculated air, and a cooler at the intake side of said blower forcondensing moisture from the circulated air; and a trough for collectingthe condensed moisture. 23. The apparatus defined in claim 22, furthercomprising means for passing said fluid through said cooling means priorto admitting same to said housing.

1. An apparatus for the treatment of photographic materials, comprising:a housing; roller means defining a transport path for a photographicmaterial having a sensitive face and a reverse face; means forming atleast one open-work surface engageable with said reverse face of thephotographic material and displaceable to entrain said photographicmaterial along said path; means for treating said sensitive face with afluid and including fluid-displacement means having an intake sidecommunicating with said housing on the side of said path opposite saidsensitive face and a discharge side communicating with the interior ofsaid surface outwardly of the sensitive face of photographic materialdisposed thereon, said means forming said surface being the surface ofsaid roller means, said roller means comprising a plurality of tubularrollers spaced apart along said path and provided with radial boresopening at the surfaces of said rollers, said intake side of saidfluid-displacement means communicating with the interiors of saidrollers; and a support frame receivable in said housing and having apair of uprights carrying said rollers, at least one of said uprightsbeing hollow and forming a duct connecting the interiors of said rollerswith said intake side of said fluid-displacement means.
 2. The apparatusdefined in claim 1, further comprising drive means including at leastone flexible endless element passing about two of said rollers forrotating same.
 3. The apparatus defined in claim 1, further comprising apair of upright lateral walls flanking said rollers and received in saidhousing, said walls being formed with bores and with cylindrical sleevesreceivable in said bores, said rollers being rotatably mounted on theexteriors of said sleeves and communicating therethrough with saidintake side of said fluid-displacement means.
 4. The apparatus definedin claim 1 wherein said uprights are formed with downwardly projectingtubular fittings receivable in upwardly open sockets formed at thebottom of said housing and communicating with said intake side of saidfluid-displacement means.
 5. The apparatus defined in claim 1 whereinsaid rollers are each subdivided into two portions, each communicatingwith the interior of a respective hollow upright and connected therebyto said intake side of said fluid-displacement means.
 6. The apparatusdefined in claim 1 wherein said means for treating said sensitive facewith said fluid includes a partition extending substantially parallel tosaid path and defining a compartment within said housing along a side ofsaid partition opposite that juxtaposed with said path, said partitionbeing perforated, and means connecting said discharge side of saidfluid-displacement means with said compartment.
 7. The apparatus definedin claim 6 wherein said discharge side is provided with an outletopening into said compartment, said outlet being formed with a bafflefor deflecting fluid parallel to said partition.
 8. The apparatusdefined in claim 1 wherein said photographic material is to be treatedwith a number of fluids, said apparatus comprising a plurality ofvessels each having such a housing, roller means and surface, saidapparatus further comprising deflector means for diverting thephotogRaphic material from one housing into the other housing, saiddeflector means including a roller conveyor disposed above the path ofsaid one housing and leading to the path of said other housing.
 9. Theapparatus defined in claim 8 wherein said roller conveyor comprises aplurality of shafts lying along an arc between said housing, and aplurality of axially spaced rollers mounted on each shaft with therollers of adjacent shafts in interdigitating relation.
 10. An apparatusfor the treatment of photographic material, comprising: a housing;roller means defining a transport path for a photographic materialhaving a sensitive face and a reverse face; means forming at least oneopen-work surface engageable with said reverse face of the photographicmaterial and displaceable to entrain said photographic material alongsaid path; means for treating said sensitive face with a fluid andincluding fluid-displacement means having an intake side communicatingwith said housing on the side of said path opposite said sensitive faceand a discharge side communicating with the interior of said surfaceoutwardly of the sensitive face of photographic material disposedthereon, said roller means including a pair of spaced-apart rollers andsaid surface being defined by at least one conveyor band extendingaround said rollers; and means for displacing one of said rollersrelative to the other to tension said band.
 11. The apparatus defined inclaim 10 wherein said band is preforated.
 12. An apparatus for thetreatment of photographic materials, comprising: a housing; roller meansdefining a transport path for a photographic material having a sensitiveface and a reverse face; means forming at least one open-work surfaceengagable with said reverse face of the photographic material anddisplaceable to entrain said photographic material along said path;means for treating said sensitive face with a fluid and includingfluid-displacement means having an intake side communicating with saidhousing on the side of said path opposite said sensitive face and adischarge side communicating with the interior of said surface outwardlyof the sensitive face of photographic material disposed thereon, saidroller means including at least one pair of spaced-apart rollers andsaid surface being formed by an endless perforated conveyor bandextending around said rollers; and stationary support members spacedapart along said path and engaged by said band, said support membersopening into the space enclosed by said band, said intake side of saidfluid-displacement means communicating with said space through saidmembers.
 13. An apparatus for the treatment of photographic materials,comprising: a housing; roller means defining a transport path for aphotographic material having a sensitive face and a reverse face; meansforming at least one open-work surface engageable with said reverse faceof the photographic material and displaceable to entrain saidphotographic material along said path; means for treating said sensitiveface with a fluid and including fluid-displacement means having anintake side communicating with said housing on the side of said pathopposite said sensitive face and a discharge side communicating with theinterior of said surface outwardly of the sensitive face of photographicmaterial disposed thereon, said roller means including at least one pairof spaced-apart rollers and said surface being formed by an endlessperforated conveyor band extending around said rollers; said rollersbeing spaced apart vertically in said housing, the lowermost rollerbeing tubular; and openings in said lowermost roller communicating withsaid intake side of said fluid-displacement means, said lowermostrollers being provided with axially spaced rings freely rotatablethereon and engaging said band.
 14. An apparatus for the treatment ofphotographic materials, comprising: a housing; rolleR means defining atransport path for a photographic material having a sensitive face and areverse face; means forming at least one open-work surface engageablewith said reverse face of the photographic material and displaceable toentrain said photographic material along said path; means for treatingsaid sensitive face with a fluid and including fluid-displacement meanshaving an intake side communicating wtih said housing on the side ofsaid path opposite said sensitive face and a discharge sidecommunicating with the interior of said surface outwardly of thesensitive face of photographic material disposed thereon; a conduitconnecting said discharge side of said fluid-displacement means with theinterior of said housing: and a valve in said conduit for controllingthe fluid-pressure differential across photographic material on saidsurface.
 15. The apparatus defined in claim 14 wherein said roller meansincludes a pair of rollers spaced apart along said path and said meansforming said surface is at least one conveyor belt passing endlesslyaround said rollers, said apparatus further comprising a pair ofvertical lateral walls flanking said belt and defining therewith a firstchamber surrounding by said belt and a second chamber between said beltand walls of said housing, at least one of said lateral walls beingformed with an opening communicating with said first chamber andconnected to said intake side of said fluid-displacement device, one ofsaid lateral walls being formed with a slot extending parallel to saidbelt and opening into said second chamber while communicating with saiddischarge side of said fluid-displacement device.
 16. The apparatusdefined in claim 14 wherein said path has a downwardly extending stretchand an upwardly extending stretch in said housing, said apparatusfurther comprising deflector means at the bottom of said path divertingthe photographic material from said downward stretch into said upwardstretch, said deflector means comprising a pair of rollers flanking saidpath and a third roller disposed therebelow, and an endless deflectorband passing around said rollers of said deflecting means for retainingsaid photographic material against said surface during the transitionfrom said downward stretch to said upward stretch.
 17. An apparatus forthe treatment of photographic materials, comprising: a housing; rollermeans defining a transport path for a photographic material having asensitive face and a reverse face; means forming at least one open-worksurface engageable with said reverse face of the photographic materialand displaceable to entrain said photographic material along said path;means for treating said sensitive face with a fluid and includingfluid-displacement means having an intake side communicating with saidhousing on the side of said path opposite said sensitive face and adischarge side communicating with the interior of said surface outwardlyof the sensitive face of photographic material disposed thereon, saidhousing defining a drying chamber downstream of a system for thechemical treatment of photographic material, said drying chamber havinga blower for directing air against said photographic material on saidsurface and for drawing air from said housing beyond said surface;cooling means in the path of air circulated by said blower fromcondensing water therefrom; and means for collecting the condensedwater.
 18. The apparatus defined in claim 17 wherein said path isgenerally U-shaped and said surface is a perforated band extendingendlessly around said path, said cooling means being disposed within thespace surrounded by said band.
 19. The apparatus defined in claim 18,further comprising a perforated partition extending parallel to saidpath and closely spaced therefrom, said blower communicating with saidhousing between said partition and an outer housing wall, the total areaof the perforations of said partitions being greatEr than the area ofthe perforations of said band.
 20. The apparatus defined in claim 17wherein said drying chamber is provided downstream of a chamber for theliquid treatment of said photographic material with an aqueous solution,said apparatus further comprising means for passing water through saidcooling means and thereupon into said treatment chamber.
 21. Theapparatus defined in claim 16 wherein said drying chamber is provideddownstream of a treatment chamber for contacting said photographicmaterial with a liquid, further comprising means for deliveringcondensed water from said cooling means to said treatment chamber. 22.An apparatus for the treatment of photographic materials, comprising: ahousing; roller means defining a transport path for a photographicmaterial having a sensitive face and a reverse face; means forming atleast one open-work surface engageable with said reverse face of thephotographic material and displaceable to entrain said photographicmaterial along said path; means for treating said sensitive face with afluid and including fluid-displacement means having an intake sidecommunicating with said housing on the side of said path opposite saidsensitive face and a discharge side communicating with the interior ofsaid surface outwardly of the sensitive face of photographic materialdisposed thereon; means downstream of said housing for contacting saidphotographic material with a stream of drying air subsequent to itstreatment with said fluid, the last-mentioned means including: a blowerfor the circulation of air, heating means at a discharge side of saidblower for heating the circulated air, and a cooler at the intake sideof said blower for condensing moisture from the circulated air; and atrough for collecting the condensed moisture.
 23. The apparatus definedin claim 22, further comprising means for passing said fluid throughsaid cooling means prior to admitting same to said housing.